Laminar Flow Control and Drag Reduction using Biomimetically ‎Inspired Forward Facing Steps

Document Type : Research Paper

Authors

1 School of Aerospace Engineering, The University of Nottingham Ningbo China, 199 Taikang East Road, Ningbo 315100, China‎

2 School of Astronautics, Northwestern Polytechnical University,127 Youyi West Road, Xi’an 710072, China

3 School of Aeronautics, Northwestern Polytechnical University,127 Youyi West Road, Xi’an 710072, China‎

4 Faculty of Science, Engineering and Computing, Kingston University London, Friars Avenue, London SW15 3DW, United Kingdom‎

Abstract

This paper explores the use of shark-skin inspired two-dimensional forward facing steps to attain laminar flow control, delay boundary layer transition and to reduce drag. Computation Fluid Dynamics (CFD) simulations are carried out on strategically placed forward facing steps within the laminar boundary layer using the Transition SST model in FLUENT after comprehensive benchmarking and validation of the simulation setup. Results presented in this paper indicate that the boundary layer thickness to step height ratio (d/h), as well as the location of the step within the laminar boundary layer (x/L), greatly influence transition onset. The presence of a strategically placed forward facing step within the laminar boundary layer might damp disturbances within the laminar boundary layer, reduce wall shear stress and energize the boundary layer leading to transition onset delay and drag reduction as compared to a conventional flat plate. Results presented in this paper indicate that a transition delay of 20% and a drag reduction of 6% is achievable, thereby demonstrating the veracity of biomimicry as a potential avenue to attain improved aerodynamic performance.

Keywords

Main Subjects

[1]      D. M. Bushnell, “Aircraft drag reduction—a review,” Proc. Inst. Mech. Eng. Part G J. Aerosp. Eng., 217(1), pp. 1–18, 2003.
[2]      P. Ball, “Life's lessons in design,” Nature, 409, pp. 413–416, 2001.
[3]      R. Cahn, “Learning from nature,” Nature, 444(7118), pp. 425–425, 2006.
[4]      D. Bhatia and J. Wang, “Biomimetics - A Potential Solution to Drag Reduction in Modern Aerodynamics,” Glob. J. Eng. Sci., 3(4), pp. 1-2, 2019.
[5]      D. Bhatia et al., “Transition Delay and Drag Reduction using Biomimetically Inspired Surface Waves,” J. Appl. Fluid Mech., 13(4), pp. 1207–1222, 2020.
[6]      G. D. Bixler and B. Bhushan, “Fluid drag reduction with shark-skin riblet inspired microstructured surfaces,” Adv. Funct. Mater., 23(36), pp. 4507–4528, 2013.
[7]      J. K. Eaton and J. P. Johnston, “A Review of Research on Subsonic Turbulent Flow Reattachment,” AIAA J., 19(9), pp. 1093–1100, 1981.
[8]      L. Chen, K. Asai, T. Nonomura, G. Xi, and T. Liu, “A review of Backward-Facing Step (BFS) flow mechanisms, heat transfer and control,” Thermal Science and Engineering Progress, 6, pp. 194–216, 2018.
[9]      E. Montazer, H. Yarmand, E. Salami, M. R. Muhamad, S. N. Kazi, and A. Badarudin, “A brief review study of flow phenomena over a backward-facing step and its optimization,” Renewable and Sustainable Energy Reviews, 82, pp. 994–1005, 2018.
[10]    A. S. Kherbeet et al., “Heat transfer and fluid flow over microscale backward and forward facing step: A review,” International Communications in Heat and Mass Transfer, 76, pp. 237–244, 2016.
[11]    Y. XUE, J. REN, J. LUO, and S. FU, “Drag increment induced by a small-scale forward-facing step in Mach number 5 turbulent boundary layer flows,” Chinese J. Aeronaut., 33(10), pp. 2491–2498, 2020.
[12]    C. A. Edelmann and U. Rist, “Impact of forward-facing steps on laminar-turbulent transition in transonic flows,” AIAA J., 53(9), pp. 2504–2511, 2015.
[13]    H. Stüer, A. Gyr, and W. Kinzelbach, “Laminar separation on a forward facing step,” Eur. J. Mech. - B/Fluids, 18(4), pp. 675–692, 1999.
[14]    J. F. Largeau and V. Moriniere, “Wall pressure fluctuations and topology in separated flows over a forward-facing step,” Exp. Fluids, 42(1), pp. 21–40, 2006.
[15]    D. Leclercq, M. Jacob, A. Louisot, and C. Talotte, “Forward-backward facing step pair - Aerodynamic flow, wall pressure and acoustic characterisation,” in 7th AIAA/CEAS Aeroacoustics Conference and Exhibit, 2001.
[16]    M. Sherry, D. Lo Jacono, and J. Sheridan, “An experimental investigation of the recirculation zone formed downstream of a forward facing step,” J. Wind Eng. Ind. Aerodyn., 98(12), pp. 888–894, 2010.
[17]    M. Agelinchaab and M. F. Tachie, “PIV Study of Separated and Reattached Open Channel Flow Over Surface Mounted Blocks,” J. Fluids Eng., 130(6), p. 061206, 2008.
[18]    R. Camussi, M. Felli, F. Pereira, G. Aloisio, and A. Di Marco, “Statistical properties of wall pressure fluctuations over a forward-facing step,” Phys. Fluids, 20(7), p. 075113, 2008.
[19]    H. Hattori and Y. Nagano, “Investigation of turbulent boundary layer over forward-facing step via direct numerical simulation,” Int. J. Heat Fluid Flow, 31(3), pp. 284-294, 2010.
[20]    R. Hillier and N. J. J. Cherry, “The effects of stream turbulence on separation bubbles,” J. Wind Eng. Ind. Aerodyn., 8(1–2), pp. 49–58, 1981.
[21]    G. Bergeles and N. Athanassiadis, “The flow past a surface-mounted obstacle,” J. Fluid Eng., 105, pp. 461–463, 1983.
[22]    I. P. P. Castro and M. Dianat, “Surface flow patterns on rectangular bodies in thick boundary layers,” J. Wind Eng. Ind. Aerodyn., 11(1–3), pp. 107–119, 1983.
[23]    Y. X. Wang and M. Gaster, “Effect of surface steps on boundary layer transition,” Exp. Fluids, 39(4), pp. 679–686, 2005.
[24]    M. Gaster, “Establishment of laminar boundary layer flow on an aerofoil body,” Google Patents, 2008.
[25]    Y. Lin, S. Raghunathan, B. Raghunathan, and S. McIlwain, “Prediction of boundary layer transition on a flat plate subject to surface waviness,” Proc. Inst. Mech. Eng. Part G J. Aerosp. Eng., 226(1), pp. 42–54, 2012.
[26]    G. B. Schubauer and P. S. Klebanoff, “Contributions on the mechanics of boundary-layer transition.,” NACA TN 3489, 1955.
[27]    F. R. Menter, R. Langtry, S. Völker, and P. G. Huang, “Transition Modelling for General Purpose CFD Codes,” Eng. Turbul. Model. Exp., 6, pp. 31–48, 2005.
[28]    F. R. Menter, R. B. Langtry, S. R. Likki, Y. B. Suzen, P. G. Huang, and S. Völker, “A Correlation-Based Transition Model Using Local Variables - Part I: Model Formulation,” J. Turbomach., 128(3), p. 413, 2006.
[29]    R. B. Langtry, F. R. Menter, S. R. Likki, Y. B. Suzen, P. G. Huang, and S. Völker, “A Correlation-Based Transition Model Using Local Variables-Part II: Test Cases and Industrial Applications,” J. Turbomach., 128(3), p. 423, 2006.
[30]    P. Malan, K. Suluksna, and E. Juntasaro, “Calibrating the Gamma-Re_theta Transition Model for Commercial CFD,” in 47th AIAA Aerospace Sciences Meeting including The New Horizons Forum and Aerospace Exposition, 2009.
[31]    J. Scott, “Aerospaceweb.org | Ask Us - Airliner Takeoff Speeds,” 2002. [Online]. Available: http://www.aerospaceweb.org/question/performance/q0088.shtml. [Accessed: 30-Aug-2017].